mmc: sdhci-msm: Update mmc DDR timing mode

A new timing mode has been introduced to differentiate SD/MMC
DDR timing modes. Use the MMC specific DDR timing mode in addition
to the SD specific one when checking for timing modes.

Change-Id: Id151c0fd0dc8eccdec8f842a5ee13af415b7ffe6
Signed-off-by: Venkat Gopalakrishnan <venkatg@codeaurora.org>